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Hydrogen Sulphide (H₂S) has been encountered within a number of Bowen Basin collieries, Central Queensland, Australia. High concentration occurrence during mining of a longwall panel raises a number of potential problems which demand greater understanding to allow efficient mining while maintaining safe and healthy environmental conditions. Longwall panels at Mine A and Mine B have recently mined through H₂S zones. The high H₂S zone mined through at Mine A was wide and covering the whole length of the face comparing to the narrow H₂S zone which was cutting the panel at 45 degree at Mine B. Longwall panels had been sampled for H₂S in pre-mining phases with vertical and inseam exploration boreholes and rib sampling of gateroad development headings. During mining face coal samples were collected in an intensive program and tested in a drum tumbler to determine an “indicated” seam concentration level through contouring that could be used to calculate the concentrations of H₂S liberated to the atmosphere. Data was analysed to determine a geostatistical method which would best represent the “indicated” seam concentration level from the given data and the block dimension of the data set. This study discusses the different sampling methods used, selection of the most suitable geostatistical method and the impact of grid size on results of data analysis. Some general observations are made correlating “indicated” seam H₂S concentrations from production face sampling with both predictions made from exploration and liberation rates during mining of the longwall panel.